British team head for Africa to search for UK summer migrants

09/10/2009 11:24:43

Male Yellow wagtail. Credit Andy Hay (rspb-images.com).

UK researchers fly south to investigate summer migrant declinesOctober 2009. The British Trust for Ornithology (BTO) and the RSPB, have joined forces to mount the largest research project of its type to understand more about our birds that spend the winter south of the Sahara desert.

Cuckoo, turtle dove, nightingale and wood warbler - Big declinesSome of the greatest declines of birds in the UK are among those species, including the cuckoo, turtle dove, nightingale and wood warbler, which spend the summer in Europe but winter in Africa. Recent figures suggest that more than 40 per cent of all migratory species passing between Europe and Africa have declined in the last three decades. Alarmingly, one in 10 of these are considered to be of global conservation concern.

Ghana & Burkina FassoThe project will involve researchers monitoring birds along a corridor stretching from Ghana's Atlantic coast to northern Burkina Faso, spanning a range of habitats from coastal rainforest to the edge of the Sahara desert.The RSPB's Dr Danaë Sheehan, who will be monitoring birds in West Africa, said: "The drastic declines of some of our best-loved summer-visiting birds, such as the cuckoo, turtle dove and nightingale, is one of the greatest concerns currently raging in conservation.

Spotted flycatchers have declined by 38 percent,but little is known about how it fares in its winter quarters in Africa.Photo credit Andy Hay/RSPBimages.com

"Although we have a reasonable understanding of these birds in the UK, we have little or no idea what's happening to these birds in their wintering grounds, but it's clear that without help these declines are likely to continue, reducing the populations of these summer visitors to dangerously low levels."

Dr Chris Hewson, Research Ecologist at the BTO, commented: "If we are to reverse these alarming declines we need to act now. To do this we need to better understand where these birds spend the winter months and what pressures they face there. If we can find this out we will be in a strong position to help secure their future."

Unknown problemsHe added. "Ongoing research is focussed on the potential causes of the declines during the breeding season here in the UK. However, problems on the wintering grounds could also be driving the declines, in particular, the predicted increase in the human population and the associated change of land use. These birds are facing a double whammy, and to help them we need to be looking at both ends of their migration."

A number of potential causes for the declines of migrants have been suggested, including: climate change, changes in rainfall patterns, and land degradation. Predicted increases in human population and climatic variability in West Africa are likely to exacerbate these threats.

2/3 of declining UK birds are summer migrantsOf 105 widespread countryside birds in the UK, eight out of twelve of those declining most rapidly since the mid 1990s are summer migrants.

According to the latest bird population estimates, published in the 2008 Breeding Bird Survey, the following summer migrants are suffering the greatest population declines between 1995 and 2007:

Turtle dove,-66 per cent

Wood warbler,-60 per cent

Pied flycatcher, -51 per cent

Yellow wagtail, -49 per cent

Whinchat, -43 per cent

Nightingale, -41 per cent

Spotted flycatcher, -38 per cent

Cuckoo, -37 per cent.

RingingThe team of researchers will be counting and ringing birds at several ‘points' in both Ghana and Burkina Faso, across a breadth of habitats, from dense tropical rainforest to semi-desert. By recording birds at these points several times during the year, researchers hope to build up a detailed picture of the movements and habitat preferences of European migratory birds wintering in Africa.

Difficult conditionsThe conditions for fieldwork will be extreme, especially in the semi-desert areas where temperatures are expected to reach 40 degrees Celsius in the shade. High humidity, elephants and malaria-carrying mosquitoes are some of the other hazards faced by field workers.

The UK project partners are the RSPB and the British Trust for Ornithology. In Africa they will be joined by the Ghana Wildlife Society and Naturama, the BirdLife International partners in Ghana and Burkina Faso. Also involved will be Dansk Ornitologisk Forening (DOF), the BirdLife Partner in Denmark, who are currently looking to establish a permanent operational base in Ghana, and Vogelbescherming Nederland (VBN), who are the supporting partner of Naturama.

The Sussex Ornithological Society has provided £5000 towards the project, and Porzana Ltd, a supplier and manufacturer of bird rings, have donated the rings.